The invention concerns a chopper for breaking up stalks, chiefly for breaking up straw behind the hopper end of a combine, with a chopper housing in which a rotor equipped with cutting tools and a drive is housed and which is positioned under a feed hopper, whose front and rear walls run down to and delimit the feed slot of the rotor, with a baffle plate forming a chopper floor, in whose area the counterblades are positioned, and with an outlet and an air discharge hood positioned above this outlet, which is delimited at its upper and lower edges from the feed hopper and the outlet by dust baffles positioned on the blade jacket cylinder.
A straw chopper of this type is known from DE 195 30 028 A1. In this known straw chopper the jacket-like air ring containing and rotating with the rotor is interrupted by the fact that the straw baffle plate located under the hopper end and forming the rear wall of the feed hopper is curved in such manner that the upper curved end lies under the hopper, while the lower end runs approximately perpendicular into the feed of the chopper housing. The task of the invention is to create a chopper of the type initially described, in which the circulation created by the rotor is even more strongly deflected or interrupted so that the take-up of the straw by the chopper is further encouraged.